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1.
Clin Exp Obstet Gynecol ; 43(2): 192-7, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27132408

RESUMEN

PURPOSE: To investigate the relationship between the change of daily step counts and low back pain (LBP) during pregnancy. Materials and METHODS: Pregnant women at less than eight weeks of gestation (WG) were recruited. Daily step counts were measured with a pedometer. To assess LBP, the Oswestry disability index (ODI) score was recorded. Thirty-six individuals were divided into the LBP and non-LBP groups. The effect of step counts on LBP between the two groups was analyzed. RESULTS: At 16-19 WG, step counts were not considerably changed in the non-LBP group but were significantly increased in the LBP group. At 24-27 and 32-35 WG, step counts were increased in the non-LBP group but were significantly decreased in the LBP group. CONCLUSIONS: Acute increase of daily step counts in early pregnancy is a risk for LBP, and gradual increases of step counts after mid-pregnancy is recommended for women.


Asunto(s)
Dolor de la Región Lumbar/epidemiología , Actividad Motora , Complicaciones del Embarazo/epidemiología , Caminata , Actigrafía , Adulto , Estudios de Cohortes , Femenino , Humanos , Embarazo , Estudios Prospectivos
2.
Neuromuscul Disord ; 18(12): 967-9, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18789688

RESUMEN

The frequency of HLA-DRB1*15 polymorphism, which is strongly associated to multiple sclerosis, was investigated in 84 adult patients with chronic dysimmune polyneuropathy and 272 healthy controls. No significant differences were detected between cases and controls and, among patients, according to gender, peripheral nerve antigen antibody seropositivity, and electrophysiological features. A trend towards an increase of HLA-DRB1*11 in anti-MAG neuropathy was detected.


Asunto(s)
Antígenos HLA-DR/genética , Polimorfismo Genético , Polineuropatías/genética , Anciano , Enfermedad Crónica , Ensayo de Inmunoadsorción Enzimática , Femenino , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Antígenos HLA-DR/metabolismo , Cadenas HLA-DRB1 , Humanos , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Polineuropatías/metabolismo , Polineuropatías/patología
3.
Kyobu Geka ; 60(10): 871-8, 2007 Sep.
Artículo en Japonés | MEDLINE | ID: mdl-17877003

RESUMEN

OBJECTIVES: We evaluated the efficacy of perioperative administration of steroid and erythromycin in surgery for lung cancer complicated with interstitial pneumonia (IP) to prevent postoperative acute exacerbation. PATIENTS AND METHODS: We operated on 21 lung cancer patients with IP for 10 years. The patients were given 400 mg of erythromycin over 1 week before surgery and re-administered on the 1st operative day. The patients were also given 125 mg of methylprednisolone intravenously just before operation and continued until the 2nd operative day. RESULTS: Lobectomy was performed in 16, segmentectomy or partial resection in 2 each, and completion pneumonectomy in 1. Three patients developed acute exacerbation of IP, but it occurred after the re-operation due to postoperative complications in 2. We experienced no operative death within 30 days, however, 2 died during the hospital stay due to multiple organ failure and sepsis. Seven of 21 patients had postoperative complications; air leakage over 1 week in 4, arrhythmia in 3, and atelectasis, postoperative bleeding, and pneumonia in 1 each, the morbidity rate was 33%. CONCLUSIONS: We conclude that the administration of steroid and erythromycin in surgery for lung cancer with IP was suspected the usefulness to prevent a postoperative acute exacerbation of IP.


Asunto(s)
Antiinflamatorios/administración & dosificación , Eritromicina/administración & dosificación , Enfermedades Pulmonares Intersticiales/tratamiento farmacológico , Neoplasias Pulmonares/cirugía , Metilprednisolona/administración & dosificación , Complicaciones Posoperatorias/prevención & control , Anciano , Quimioterapia Combinada , Femenino , Humanos , Enfermedades Pulmonares Intersticiales/complicaciones , Masculino , Persona de Mediana Edad , Atención Perioperativa , Neumonectomía
4.
Kyobu Geka ; 59(1): 36-40, 2006 Jan.
Artículo en Japonés | MEDLINE | ID: mdl-16440683

RESUMEN

OBJECTIVE: To find out the optimal surgical indication in stage IV lung cancer patients, we evaluated them retrospectively. METHODS & RESULTS: From 1975 to 2005, 62 patients without multiple metastases were operated at our hospital. The most common histological type was adenocarcinoma (67.7%). The metastatic lesions were lung (33.9%), brain (24.2%), liver, bone, adrenal gland and so on. The overall survival rate of stage IV lung cancer was 10.4% at 5-year. Five-year survival for patients with lung or brain metastasis who had no lymph node metastasis were significantly more superior than those with lymph node metastasis (p=0.0389, 0.0021). Four of 62 patients had 5-year survival. Two were lung and the others were brain and adrenal gland metastasis without lymph node metastasis. CONCLUSION: Stage IV lung cancer with lung or brain or adrenal gland metastasis without lymph node metastasis should be resected.


Asunto(s)
Neoplasias Pulmonares/patología , Neoplasias Pulmonares/cirugía , Adenocarcinoma/mortalidad , Adenocarcinoma/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias Encefálicas/mortalidad , Neoplasias Encefálicas/secundario , Femenino , Humanos , Neoplasias Pulmonares/mortalidad , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias/mortalidad , Estudios Retrospectivos , Análisis de Supervivencia
5.
Eur J Surg Oncol ; 31(8): 882-90, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15993031

RESUMEN

AIMS: In a previous pilot study, we reported the usefulness of the modified the Cancer of the Liver Italian Program (CLIP) score for patients with hepatocellular carcinoma (HCC). To determine the best staging system for predicting the survival of HCC patients, we conducted a comparative analysis of prognosis using multivariate analysis in 210 Japanese HCC patients who underwent hepatic resection. METHODS: We compared the survival as predicted by various staging systems, including tumour node metastasis (TNM) stage of the American Joint Commission on Cancer (AJCC) and the Liver Cancer Study Group of Japan, the Japan Integrated Staging (JIS) score (Japanese TNM and Child-Pugh classification), CLIP score and our modified CLIP score using protein induced by vitamin K absence or antagonist II (PIVKA-II). RESULTS: Univariate analysis showed that discrimination of disease-free survival in the early and advanced stages by the JIS score and modified CLIP score was clearer than by the Japanese or AJCC TNM or the original CLIP score. Discrimination between stages of overall survival by all staging systems was significant. Multivariate analysis showed that the JIS, CLIP and modified CLIP scores were better staging systems for predicting survival than the Japanese and AJCC TNM. The modified CLIP score showed the lowest Akaike information criteria statistical value for disease-free and overall survival, which means the best discrimination ability for patient survival compared with the JIS score and CLIP score. CONCLUSIONS: A staging system that combines tumour factors, sensitive tumour marker(s) and hepatic function is the best predictor of prognosis of HCC patients.


Asunto(s)
Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/patología , Estadificación de Neoplasias/métodos , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores/análisis , Biomarcadores de Tumor/análisis , Carcinoma Hepatocelular/fisiopatología , Carcinoma Hepatocelular/cirugía , Supervivencia sin Enfermedad , Femenino , Predicción , Hepatectomía , Humanos , Hígado/fisiopatología , Neoplasias Hepáticas/fisiopatología , Neoplasias Hepáticas/cirugía , Metástasis Linfática/patología , Masculino , Persona de Mediana Edad , Análisis Multivariante , Terapia Neoadyuvante , Recurrencia Local de Neoplasia/patología , Estadificación de Neoplasias/estadística & datos numéricos , Precursores de Proteínas/análisis , Protrombina/análisis , Estudios Retrospectivos , Tasa de Supervivencia
6.
J Neurol Neurosurg Psychiatry ; 75(11): 1611-3, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15489397

RESUMEN

Brain involvement in myotonic dystrophy type 1 (DM1) is characterised by cortical atrophy and white matter lesions. We compared the magnetic resonance imaging derived grey matter maps of 22 DM1 patients with those of matched, healthy controls using voxel based morphometry to evaluate the extension of global and regional cortical atrophy in DM1, as well as its relationships with clinical and genetic features. Patients had significantly reduced brain tissue volumes. Grey matter volume was inversely correlated with age; this inverse correlation was significantly stronger in DM1 than in controls. Neither the clinical and genetic characteristics nor white matter lesions were correlated with cortical atrophy. Grey matter atrophy was located mainly in the bilateral frontal and parietal lobes, in the bilateral middle temporal gyrus, and in the left superior temporal and occipital gyrus.


Asunto(s)
Corteza Cerebral/patología , Procesamiento de Imagen Asistido por Computador , Imagenología Tridimensional , Imagen por Resonancia Magnética , Distrofia Miotónica/diagnóstico , Adulto , Atrofia , Mapeo Encefálico , Aberraciones Cromosómicas , Cromosomas Humanos Par 19 , Progresión de la Enfermedad , Femenino , Genes Dominantes/genética , Humanos , Masculino , Cómputos Matemáticos , Persona de Mediana Edad , Distrofia Miotónica/genética , Examen Neurológico , Valores de Referencia , Programas Informáticos , Repeticiones de Trinucleótidos/genética
7.
Eur J Surg Oncol ; 30(7): 765-70, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15296991

RESUMEN

AIMS: The new Japanese staging system for hepatocellular carcinoma (HCC), the Japan integrated staging (JIS) score, accounts for both Child-Pugh classification and Japan tumour node metastasis (TNM) staging. However, in HCC patients who undergo hepatectomy, liver function is relatively good and a better prognostic classification of hepatic function is necessary. METHODS: The present study was designed to analyse the modified JIS score using liver damage grade by the Liver Cancer Study Group of Japan instead of the Child-Pugh classification (using the category indocyanine green retention rate at 15 min [ICG(R15)] instead of encephalopathy), and to compare the Japan TNM stage in 101 patients who underwent resection of HCC. RESULTS: The liver damage grade showed significantly better discrimination of disease-free and overall survival than did the Child-Pugh classification. The modified JIS score system showed significant differences of disease-free and overall survivals in each score and this system was superior for discriminating survivals compared with the TNM staging. CONCLUSIONS: The combined staging system of hepatic function, particularly ICG(R15), and tumour stage provides a better prediction of prognosis. The JIS score using the liver damage grade was a useful predictor of prognosis of HCC patients who underwent hepatic resection.


Asunto(s)
Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/patología , Estadificación de Neoplasias , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma Hepatocelular/mortalidad , Supervivencia sin Enfermedad , Femenino , Humanos , Japón/epidemiología , Neoplasias Hepáticas/mortalidad , Masculino , Persona de Mediana Edad , Análisis de Supervivencia
8.
Neuropediatrics ; 34(6): 307-10, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-14681756

RESUMEN

We report on a 14-month-old boy who had acute multiple infarcts in the posterior circulation due to an extremely early onset of spontaneous vertebral artery dissection. Despite the absence of clinical signs of connective tissue disorders, an ultrastructural change of collagen fibrils and elastic fibers indicated connective tissue abnormalities. Arterial dissection should be considered as a cause of stroke during infancy.


Asunto(s)
Tejido Elástico/ultraestructura , Colágenos Fibrilares/ultraestructura , Disección de la Arteria Vertebral/patología , Humanos , Lactante , Masculino
9.
Eur J Surg Oncol ; 29(9): 735-42, 2003 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-14602492

RESUMEN

AIMS: The new staging system proposed by the Cancer of the Liver Italian Program (CLIP) for hepatocellular carcinoma (HCC) accounts for both liver dysfunction and tumour characteristics. The present study was designed to analyze UICC TNM stage, CLIP and modified CLIP in 91 patients who underwent hepatic resection for HCC. METHODS: In the modified CLIP, scoring of AFP was replaced by that of protein induced by vitamin K absence or antagonist II (PIVKA-II; predictive value, > or = 400 mAU/ml). RESULTS: After hepatic resection, 54 patients developed recurrent tumours. High PIVKA-II was a significant determinant of recurrence (p<0.05). However, a high score of the modified CLIP as well as those other staging systems did not correlate with tumour-recurrence rate. Univariate analysis showed that high TNM score, CLIP score and our modified CLIP score were significant predictors of poor prognosis. Multivariate Cox's analysis revealed that high PIVKA-II and high modified CLIP score were associated with higher risk for disease-free and overall survival as well as high TNM stage. CONCLUSIONS: Compared with the original CLIP, our modified CLIP was a better predictor of prognosis of HCC patients who underwent hepatic resection.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Biomarcadores , Carcinoma Hepatocelular/cirugía , Hepatectomía/métodos , Neoplasias Hepáticas/cirugía , Recurrencia Local de Neoplasia/cirugía , Precursores de Proteínas/metabolismo , Protrombina/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/mortalidad , Carcinoma Hepatocelular/patología , Supervivencia sin Enfermedad , Femenino , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/mortalidad , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/metabolismo , Recurrencia Local de Neoplasia/mortalidad , Recurrencia Local de Neoplasia/patología , Estadificación de Neoplasias , Valor Predictivo de las Pruebas , Análisis de Supervivencia
10.
J Neurol Neurosurg Psychiatry ; 74(7): 998-9, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12810806

RESUMEN

The cause of downbeat nystagmus (DBN) remains undiagnosed in about 40% of patients. This paper reports the presence of antiglutamic acid decarboxylase antibodies (GAD-Ab) in a patient with DBN. Antibodies against GABAergic neurons located in the vestibular complex may induce chemical denervation of the floccular neurons, which normally suppress the peripheral imbalance between vertical semicircular canal systems, thereby causing DBN. Testing for GAD-Ab may be indicated in DBN patients without an identifiable anatomical brain lesion.


Asunto(s)
Autoanticuerpos/inmunología , Glutamato Descarboxilasa/inmunología , Nistagmo Patológico/inmunología , Anciano , Autoanticuerpos/análisis , Femenino , Humanos , Nistagmo Patológico/patología , Receptores de GABA-A/fisiología
11.
Kyobu Geka ; 55(9): 785-8, 2002 Aug.
Artículo en Japonés | MEDLINE | ID: mdl-12174624

RESUMEN

Video-assisted thoracoscopic surgery (VATS) has been widely used in the treatment of spontaneous pneumothorax. The unexpectedly high increase of the recurrence rate is the most important problem. We examined the interaction between recurrence, clinical features and patient's backgrounds. The main causes of recurrence were oversight of bullae and the emphysematous changes at the periphery of the site where an autosuture device was used. 90% of the recurrence occurred in the patients with type III small diffuse bullae. Introduction of the regional talc pleurodesis and covering stapled line with absorbable mesh were extremely useful to lower the recurrence rate after VATS for spontaneous pneumothorax.


Asunto(s)
Implantes Absorbibles , Pleurodesia/métodos , Neumotórax/cirugía , Mallas Quirúrgicas , Talco , Cirugía Torácica Asistida por Video , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Terapia Combinada , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevención Secundaria
12.
Neurology ; 57(6): 1126-8, 2001 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-11571352

RESUMEN

To detect signs of axonal damage in MS, the authors investigated the occurrence in EMG of motor unit action potentials with satellite potentials (SP-MUAP) in the upper limb muscles in 10 consecutive patients with MS with cervical spinal cord demyelinating lesions and 10 control subjects. Subjects' SP-MUAP rate was 0 to 2.5% (median 0%) in the control group, and 0 to 17.5% (median 7.5%) in the MS group (p < 0.01). Motor unit remodeling secondary to axonal transection of spinal motor neurons traversing cervical demyelinating lesions may be hypothesized.


Asunto(s)
Axones/fisiología , Electromiografía , Esclerosis Múltiple/fisiopatología , Adulto , Potenciales Evocados Motores/fisiología , Femenino , Humanos , Persona de Mediana Edad , Neuronas Motoras/fisiología , Esclerosis Múltiple/diagnóstico , Músculo Esquelético/inervación , Médula Espinal/fisiopatología , Degeneración Walleriana/diagnóstico , Degeneración Walleriana/fisiopatología
13.
Cells Tissues Organs ; 169(2): 158-64, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11399856

RESUMEN

We studied corresponding structures on the oral and basal surfaces of the oral epithelial layer, focusing on the microanatomy of gustatory papillae. Specimens for scanning electron microscopy were obtained from the rat soft palates and fixed with a mixture of 2% paraformaldehyde and 1% glutaraldehyde. They were first prepared without postfixation and conductive-staining to study the oral surface. After examination, the epithelium was reinforced by additional sputter coating and treated with 6 N NaOH at 60 degrees C to exfoliate the basal epithelial surfaces without any significant artifacts. The papillae, showing circular, elliptical or fusiform protuberances on the oral surface, were classified into two types: types I and II. The type I and type II papillae contained one and two taste pores, respectively. On the basal epithelial surface, the basal portions of the taste buds were associated with concentrically arranged nerve fibers and Schwann cells. Another characteristic finding on the basal epithelial surface was the presence of excretory ducts of minor salivary glands in a close spatial relationship to taste buds. It is suggested that saliva coming out through the duct is mixed with food, thus enabling intimate contact with the taste pores of the papillae.


Asunto(s)
Epitelio/embriología , Epitelio/ultraestructura , Paladar Blando/embriología , Paladar Blando/ultraestructura , Animales , Femenino , Masculino , Microscopía Electrónica de Rastreo , Modelos Biológicos , Ratas , Ratas Wistar , Glándulas Salivales/embriología , Glándulas Salivales/ultraestructura , Papilas Gustativas/embriología
14.
Neurology ; 55(8): 1207-9, 2000 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-11071501

RESUMEN

The authors prospectively studied the natural course of cardiac involvement and its relationship to cytosine-thymine-guanine (CTG) expansion in 50 patients with myotonic dystrophy who were submitted to periodic cardiovascular EKG and EKG-Holter monitoring during a median follow-up of 56 months. Nineteen patients (38%) developed major EKG changes. CTG length was not correlated with the frequency of EKG abnormalities, but was inversely correlated with the age at onset of EKG abnormalities (p < 0.0001). CTG length influences the timing of cardiac complications in myotonic dystrophy.


Asunto(s)
Cardiopatías/genética , Cardiopatías/fisiopatología , Distrofia Miotónica/genética , Repeticiones de Trinucleótidos/genética , Adolescente , Adulto , Edad de Inicio , Niño , Electrocardiografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
15.
EMBO J ; 19(3): 434-44, 2000 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-10654941

RESUMEN

The eukaryotic translation initiation factor 4G (eIF4G) proteins play a critical role in the recruitment of the translational machinery to mRNA. The eIF4Gs are phosphoproteins. However, the location of the phosphorylation sites, how phosphorylation of these proteins is modulated and the identity of the intracellular signaling pathways regulating eIF4G phosphorylation have not been established. In this report, two-dimensional phosphopeptide mapping demonstrates that the phosphorylation state of specific eIF4GI residues is altered by serum and mitogens. Phosphopeptides resolved by this method were mapped to the C-terminal one-third of the protein. Mass spectrometry and mutational analyses identified the serum-stimulated phosphorylation sites in this region as serines 1108, 1148 and 1192. Phosphoinositide-3-kinase (PI3K) inhibitors and rapamycin, an inhibitor of the kinase FRAP/mTOR (FKBP12-rapamycin-associated protein/mammalian target of rapamycin), prevent the serum-induced phosphorylation of these residues. Finally, the phosphorylation state of N-terminally truncated eIF4GI proteins acquires resistance to kinase inhibitor treatment. These data suggest that the kinases phosphorylating serines 1108, 1148 and 1192 are not directly downstream of PI3K and FRAP/mTOR, but that the accessibility of the C-terminus to kinases is modulated by this pathway(s).


Asunto(s)
Factores de Iniciación de Péptidos/química , Proteínas Quinasas , Sirolimus/farmacología , Secuencia de Aminoácidos , Sitios de Unión , Análisis Mutacional de ADN , Electroforesis en Gel Bidimensional , Inhibidores Enzimáticos/farmacología , Factor 4G Eucariótico de Iniciación , Humanos , Espectrometría de Masas , Datos de Secuencia Molecular , Factores de Iniciación de Péptidos/genética , Mapeo Peptídico , Inhibidores de las Quinasa Fosfoinosítidos-3 , Fosfopéptidos/química , Fosforilación , Fosfotransferasas (Aceptor de Grupo Alcohol)/metabolismo , Biosíntesis de Proteínas , ARN Mensajero/metabolismo , Alineación de Secuencia , Transducción de Señal , Serina-Treonina Quinasas TOR
16.
Muscle Nerve ; 23(2): 252-8, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10639619

RESUMEN

Spinal-bulbar muscular atrophy (SBMA) is a rare X-linked neuronopathy associated with an abnormal representation of androgen receptors in the nervous system. Standard nerve conduction and histopathological studies have disclosed the involvement of large myelinated sensory fibers in the spinal nerves of SBMA patients. Little is known about the involvement of small sensory neurons and trigeminal nerves. Laser evoked potentials (LEPs) were studied in 6 unrelated patients with SBMA; 5 of these patients also underwent trigeminal reflex recordings, and 3 a sural nerve biopsy. LEPs were markedly abnormal, indicating a dysfunction in pain pathways. Given the sparing of small fibers in the sural nerve specimens, we hypothesize a dysfunction in spinothalamic cells, possibly due to an abnormal representation of the androgen receptors. Except for the jaw-jerk, all the trigeminal reflexes were markedly abnormal. Since the afferents for the jaw-jerk have their cell body within the central nervous system instead of the ganglion, the selective sparing of the jaw-jerk indicates a trigeminal ganglionopathy.


Asunto(s)
Neuropatía Hereditaria Motora y Sensorial/fisiopatología , Atrofia Muscular Espinal/fisiopatología , Fibras Nerviosas Mielínicas/fisiología , Anciano , Electrodiagnóstico , Electromiografía , Potenciales Evocados/fisiología , Neuropatía Hereditaria Motora y Sensorial/genética , Neuropatía Hereditaria Motora y Sensorial/patología , Humanos , Masculino , Persona de Mediana Edad , Atrofia Muscular Espinal/genética , Atrofia Muscular Espinal/patología , Conducción Nerviosa/fisiología , Reflejo/fisiología , Nervio Sural/patología , Ganglio del Trigémino/fisiopatología
17.
Mol Cell Biol ; 20(2): 468-77, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10611225

RESUMEN

The mammalian eukaryotic initiation factor 4GI (eIF4GI) may be divided into three roughly equal regions; an amino-terminal one-third (amino acids [aa] 1 to 634), which contains the poly(A) binding protein (PABP) and eIF4E binding sites; a middle third (aa 635 to 1039), which binds eIF4A and eIF3; and a carboxy-terminal third (aa 1040 to 1560), which harbors a second eIF4A binding site and a docking sequence for the Ser/Thr kinase Mnk1. Previous reports demonstrated that the middle one-third of eIF4GI is sufficient for cap-independent translation. To delineate the eIF4GI core sequence required for cap-dependent translation, various truncated versions of eIF4GI were examined in an in vitro ribosome binding assay with beta-globin mRNA. A sequence of 540 aa encompassing aa 550 to 1090, which contains the eIF4E binding site and the middle region of eIF4GI, is the minimal sequence required for cap-dependent translation. In agreement with this, a point mutation in eIF4GI which abolished eIF4A binding in the middle region completely inhibited ribosomal binding. However, the eIF4GI C-terminal third region, which does not have a counterpart in yeast, modulates the activity of the core sequence. When the eIF4A binding site in the C-terminal region of eIF4GI was mutated, ribosome binding was decreased three- to fourfold. These data indicate that the interaction of eIF4A with the middle region of eIF4GI is necessary for translation, whereas the interaction of eIF4A with the C-terminal region plays a modulatory role.


Asunto(s)
Fragmentos de Péptidos/química , Fragmentos de Péptidos/metabolismo , Factores de Iniciación de Péptidos/química , Factores de Iniciación de Péptidos/metabolismo , Biosíntesis de Proteínas/genética , Caperuzas de ARN/genética , Ribosomas/metabolismo , Secuencia de Aminoácidos , Sitios de Unión , Factor 4A Eucariótico de Iniciación , Factor 4E Eucariótico de Iniciación , Factor 4G Eucariótico de Iniciación , Globinas/genética , Células HeLa , Humanos , Péptidos y Proteínas de Señalización Intracelular , Modelos Biológicos , Datos de Secuencia Molecular , Fragmentos de Péptidos/genética , Factores de Iniciación de Péptidos/genética , Mutación Puntual/genética , Pruebas de Precipitina , Unión Proteica , Proteínas Serina-Treonina Quinasas/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Ribosomas/genética , Alineación de Secuencia , Eliminación de Secuencia/genética , Moldes Genéticos
18.
Arch Histol Cytol ; 62(4): 375-81, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10596948

RESUMEN

The three-dimensional architectures of the perigemmal cells and their keratin bundles in the rat circumvallate papillae were studied by transmission and scanning electron microscopy. The perigemmal cells were classified into three layers: basal, middle and upper. The basal layer consisted of polygonal cells located close to the basal lamina, the middle layer comprised longitudinally elongated cells fitting the lateral convexity of the taste bud, and the upper layer was imbricating flat cells along the upper portion of the taste bud. When fresh specimens were jointly treated with Triton X-100 and sonication, the taste buds were often detached and the cytoplasmic matrices of the perigemmal cells were effectively removed. Consequently, we were able to demonstrate an extensive network of the subplasmalemmal keratin bundles of the perigemmal cells. The framework appeared either as a thin lacework, a thick fence-like structure, or a lattice work in the basal, middle, and upper layers, respectively. The thin lacework in the basal layer was considered to be a developing process of the framework. The thick fence-like structure in the middle layer probably plays a primary role in supporting the taste bud. The latticework in the upper layer is believed to reflect a remodeling in reducing the keratin framework.


Asunto(s)
Células Epiteliales/ultraestructura , Queratinas/ultraestructura , Papilas Gustativas/citología , Papilas Gustativas/ultraestructura , Animales , Femenino , Microscopía Electrónica de Rastreo , Ratas , Ratas Wistar , Lengua/anatomía & histología , Lengua/ultraestructura
19.
Mol Cell Biol ; 19(11): 7336-46, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10523622

RESUMEN

Eukaryotic initiation factor 4A (eIF4A) is an RNA-dependent ATPase and ATP-dependent RNA helicase that is thought to melt the 5' proximal secondary structure of eukaryotic mRNAs to facilitate attachment of the 40S ribosomal subunit. eIF4A functions in a complex termed eIF4F with two other initiation factors (eIF4E and eIF4G). Two isoforms of eIF4A, eIF4AI and eIF4AII, which are encoded by two different genes, are functionally indistinguishable. A third member of the eIF4A family, eIF4AIII, whose human homolog exhibits 65% amino acid identity to human eIF4AI, has also been cloned from Xenopus and tobacco, but its function in translation has not been characterized. In this study, human eIF4AIII was characterized biochemically. While eIF4AIII, like eIF4AI, exhibits RNA-dependent ATPase activity and ATP-dependent RNA helicase activity, it fails to substitute for eIF4AI in an in vitro-reconstituted 40S ribosome binding assay. Instead, eIF4AIII inhibits translation in a reticulocyte lysate system. In addition, whereas eIF4AI binds independently to the middle and carboxy-terminal fragments of eIF4G, eIF4AIII binds to the middle fragment only. These functional differences between eIF4AI and eIF4AIII suggest that eIF4AIII might play an inhibitory role in translation under physiological conditions.


Asunto(s)
Factores de Iniciación de Péptidos/genética , Factores de Iniciación de Péptidos/metabolismo , Biosíntesis de Proteínas , Adenosina Trifosfatasas/metabolismo , Secuencia de Aminoácidos , Secuencia Conservada , ADN Helicasas/metabolismo , Células Eucariotas , Factor 4A Eucariótico de Iniciación , Factor 4G Eucariótico de Iniciación , Expresión Génica , Biblioteca de Genes , Modelos Teóricos , Datos de Secuencia Molecular , Familia de Multigenes , Unión Proteica , Isoformas de Proteínas , Ribosomas/metabolismo , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido
20.
J Neurol Sci ; 164(1): 60-3, 1999 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-10385049

RESUMEN

The aim of the present study was to assess whether or not there is any correlation between magnetic resonance imaging (MRI) abnormalities and excessive daytime sleepiness (EDS) in a consecutive series of patients with myotonic dystrophy (MD). The influences of nocturnal breathing abnormalities and sleep morphology on EDS were also evaluated. Ten MD patients were studied by means of an all-night polysomnographic recording, the multiple sleep latency test (MSLT) and MRI. Diagnosis of MD was established on the basis of the clinical and electrophysiological evidence of myotonia as well as of the characteristic genetic pattern. No patient had respiratory failure. Polysomnography and MSLT were also evaluated in ten healthy age-matched controls under the same environmental conditions. The mean MSLT value was significantly lower in patients than in controls. Five of the ten patients were found to have pathological EDS. The quantitative sleep variables and the nocturnal apnoeas in these five patients were not significantly different from those of the patients without EDS. As two patients did not undergo MRI because of claustrophobia, the MRI data were considered in eight patients. Corpus callosum (CC) atrophy was detected in four patients, whereas three patients showed hyperintense areas in the white matter. No correlation was found between EDS and MRI indexes of subcortical atrophy as well as volume of the hyperintense areas. By contrast, a correlation was found between the MSLT value and the reduction in the anterior area of the CC. Our data suggest that CC atrophy might occur in MD patients, and that the size of the CC anterior area might be associated with EDS.


Asunto(s)
Cuerpo Calloso/patología , Distrofia Miotónica/complicaciones , Trastornos del Sueño-Vigilia/etiología , Adulto , Estudios de Casos y Controles , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Distrofia Miotónica/diagnóstico , Trastornos del Sueño-Vigilia/diagnóstico
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